A conventional vehicle auxiliary system, such as a car video recorder, provided with Global Positioning System (GPS) functionality is incapable of correctly determining at which level a vehicle is when the vehicle is driving on a multi-level road system that includes at least two different levels of roads. For example, when the vehicle is driving on an elevated road which is on a higher level of the multi-level road system, the conventional vehicle auxiliary system may mistakenly provide driving assistance information that corresponds to a ground level road on a lower level of the multi-level road system.